Best Practices for Load Testing Mobile Applications | Part 2

Mobile applications and mobile websites have become a major channel for conducting business, improving employee efficiency, communicating, and reaching consumers. In Part I of this article we discussed the differences between testing traditional and mobile applications, specific challenges associated with mobile load testing, mobile testing basics and best practices for recording mobile load test scenarios. In this Part 2 of the article, we will look at how to conduct realistic tests and how to best analyze the results.

How to Run Realistic Load TestsOnce you've recorded a mobile test scenario, you need to be parameterize it so that it can emulate users with different identities and behaviors as it is played back to produce a realistic load on the server. This step is required for traditional and mobile web applications, and the tools used to complete it are the same. When playing back the test scenarios, however, there are several challenges specific to mobile load testing.

Simulating Network ConditionsToday's mobile devices generally access the server over networks that are slower than those used by desktop computers. Network conditions have a significant effect on the user experience, and the effect may be more or less pronounced depending on the application. Network characteristics including bandwidth, latency and packet loss have a huge impact on client response times and on the way the server is loaded. By simulating different network conditions in a test lab environment you can forecast the effects of changes in the network infrastructure on the application's performance. Doing so also allows you to discover application issues in the development cycle, therefore reducing costs.

Bandwidth, Latency and Packet LossFor example, low bandwidth increases the time it takes to download a resource, which then results in higher page load times. If the customer is connected longer, front-end servers hold sockets longer, load balancers have more active TCP sessions and application servers use more threads.

Mobile networks have limited bandwidth and high latency compared to Wi-Fi and broadband. Since the latency is a time added to each request and webpages are composed of many sub-requests, the time required to load a webpage on a mobile device greatly depends on the latency.

Limiting bandwidth and simulating latency and packet loss during a load test allows you to check that all of your users, including mobile users, will get the best user experience and acceptable response times while ensuring your servers won't have problems under load.

Bandwidth and Response TimesThe bandwidth is directly correlated with how long it takes to download data from the server. The lower the bandwidth, the higher the response time. A server that provides acceptable response times for desktop users using DSL or another high-speed broadband service may deliver a poor end-user experience to mobile users with lower bandwidth.

It is important to validate your service-level agreements (SLAs) and performance objectives with tests that use the same bandwidth limitations as your users to avoid making decisions based on misleading test results. Such tests must incorporate bandwidth simulation, which is the process of artificially slowing down the traffic during a test to simulate a slower connection.

Bandwidth and Server LoadClients using lower bandwidth connections also affect the server. The lower the bandwidth, the longer the connections. Longer connections, in turn, lead to more simultaneous connections on your web server and your application server. Thus, mobile users tend to consume more connections than their wired counterparts. Most servers have settings that limit the number of simultaneous connections that they can handle. Without a testing tool that realistically simulates bandwidth, these settings cannot be properly validated.

Simulating Bandwidth Limitations for Individual Virtual UsersWhen load testing, effective bandwidth simulation requires the ability to individually limit the bandwidth for each user or groups of users, independent of the others.

Consider a situation in which you need to verify performance when 100 mobile users are accessing the server. In this scenario, you'd want to simulate 100 virtual users, with each user limited to a 1Mbps 3G connection. In this case, the total bandwidth for all users is 100Mbps (100 users * 1Mbps/user). Though it is possible to use WAN emulation software or a network appliance to globally limit the bandwidth for the load generation machine to 100 Mbps (or any other arbitrary limit), in practice this does not provide a realistic test because it does not impose a strict 1Mbps constraint on each user. Bandwidth simulation support must be integrated in the load testing tool to enable bandwidth limits to be applied to individual virtual users.

To conduct an even more realistic test, you'll want to simulate a mixed population of users accessing your application with a variety of bandwidths. With a tool capable of bandwidth simulation on a per virtual user basis, you can determine the response times for users at each bandwidth across a range of bandwidths in a single test. This saves times when you need to compare the response times of web applications and business transactions for clients who have different bandwidth limits.

CIO, CTO & Developer Resources

Simulating Browsers and Browser CapabilitiesWhen a browser requests a resource from a web server, it identifies itself via the user-agent header sent with each request. This header contains information about the browser and the platform on which it is running. Servers use this information to deliver different versions of the content based on the client system. As noted earlier, many web applications deliver different content to mobile users and desktop users. Some further differentiate mobile users into subgroups based on information in the user-agent header, delivering less text and smaller images to devices with small screens. This can lead to bandwidth consumption and loading times that vary widely with the browser and platform being used.

As a result, the ability to manipulate the user-agent header is essential not only for recording test scenarios, but also for playing them back. Tools that lack this capability will fail to retrieve the appropriate content from the server.

Simulating Parallel ConnectionsMobile browsers, like desktop browsers, can generate the HTTP requests needed to retrieve the static resources of a web page in parallel. Rather than waiting for each image to finish loading before requesting the next, this approach requests multiple images at once to shorten the overall page load time. To measure response times accurately, load testing tools must replicate this behavior by generating multiple requests in parallel. Moreover, they must simulate the appropriate number of parallel connections as this number may differ from one mobile browser to another. Again, tools that lack this capability are not performing realistic tests, placing the results they deliver into question.

Identifying the Most Appropriate Settings for Realistic TestsFinding the appropriate values for key test settings - such as the user-agent, bandwidth, and number of simultaneous connections - can be a challenge. More advanced load testing tools can help testers set these values. For example, test scenario playback is greatly simplified by tools that can automatically inform the tester of which user-agent string and number of parallel connections to use based on the browser name, version, and platform. The process is further streamlined when the tools can suggest the most appropriate upload and download bandwidth settings based on the technology used (for example, Wi-Fi, 3G, 3G+, and so on) and the quality of the signal (for example, poor, average, or good).

Using the CloudYou can use load testing with the cloud after (or in conjunction with) on-premise testing in the lab to improve the realism of your tests by generating high loads and testing from different locations, while saving time and lowering costs.

Generating a High LoadFor consumer-facing apps and websites, it's often difficult to predict the number of users your applications will have to handle. Traffic spikes that results from a promotion, marketing campaign, new product release, or even unexpected social network buzz can be substantial. To generate a similar load in-house, you would need a significant investment in hardware. Using the cloud, you can generate the same high load using on-demand resources at a much lower cost.

Testing from Different GeographiesYour web application's real users likely access the server from many different geographical locations and use different networks. To properly validate the application and the server infrastructure, your virtual users should operate under similar real world conditions.

Testing the Entire Application Delivery ChainWhen your real users are located outside the firewall, you should run your virtual users from the cloud to validate the parts of the application delivery chain that are not tested when testing from the lab, including the firewall, load balancers, and other network equipment.

Tools for Testing with the CloudWhile the cloud represents an opportunity to rapidly increase the scale and improve the realism of load testing at low costs, cloud testing is most effective when it's used to complement internal load testing. Note that the primary factor in the success of load testing with the cloud is not the move to the cloud, rather it's the tool you select and how well it uses cloud technology. In particular, it's best to select a solution that is integrated with multiple cloud platforms, enables in-house test assets to be reused in the cloud, and supports realistic, large-scale tests across multiple geographical regions.

Analyzing ResultsThe default results of a load test are frequently delivered as averages. For example, load testing tools will typically show what errors occurred and the average response times for a request, web page, or business transaction regardless of the type of users being simulated or the bandwidth available to them.

Because bandwidth may vary widely for the different kinds of users simulated, the errors and response times can also vary widely. Taking an average of results with significant variation does not provide an accurate picture of what is really happening. To gain meaningful insights and to validate your SLAs and performance requirements for each network condition, it is important to go beyond the default results and analyze the results for each kind of user.

ConclusionIn many ways, mobile load testing is similar to load testing classic web applications. As a result, testers can leverage much of their existing knowledge and reuse existing techniques - like using the cloud for realistic, large-scale tests. However, there are specific requirements for testing mobile applications that are not addressed by traditional load testing techniques. Recording mobile test scenarios, conducting realistic tests that simulate real-world bandwidth and browser characteristics, and properly analyzing the results are some of the key areas that require special attention for mobile applications. Addressing challenges in these areas is essential to ensuring mobile web applications are sufficiently tested prior to release and that they will perform well under load in production.

Steve Weisfeldt is a Senior Performance Engineer at Neotys, a provider of load testing software for Web applications. Previously, he has worked as the President of Engine 1 Consulting, a services firm specializing in all facets of test automation. Prior to his involvement at Engine 1 Consulting, he was a Senior Systems Engineer at Aternity. Prior to that, Steve spent seven years at automated testing vendor Segue Software (acquired by Borland). While spending most of his time at Segue delivering professional services and training, he was also involved in pre-sales and product marketing efforts.

Being in the load and performance testing space since 1999, Steve has been involved in load and performance testing projects of all sizes, in industries that span the retail, financial services, insurance and manufacturing sectors. His expertise lies in enabling organizations to optimize their ability to develop, test and launch high-quality applications efficiently, on-time and on-budget. Steve graduated from the University of Massachusetts-Lowell with a BS in Electrical Engineering and an MS in Computer Engineering.

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.

SYS-CON Events announced today that Vitria Technology, Inc. will exhibit at SYS-CON’s @ThingsExpo, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY.
Vitria will showcase the company’s new IoT Analytics Platform through live demonstrations at booth #330. Vitria’s IoT Analytics Platform, fully integrated and powered by an operational intelligence engine, enables customers to rapidly build and operationalize advanced analytics to deliver timely business outcomes ...

The Internet of Things (IoT) promises to evolve the way the world does business; however, understanding how to apply it to your company can be a mystery. Most people struggle with understanding the potential business uses or tend to get caught up in the technology, resulting in solutions that fail to meet even minimum business goals.
In his session at @ThingsExpo, Jesse Shiah, CEO / President / Co-Founder of AgilePoint Inc., showed what is needed to leverage the IoT to transform your business. ...

Business and IT leaders today need better application delivery capabilities to support critical new innovation. But how often do you hear objections to improving application delivery like, “I can harden it against attack, but not on this timeline”; “I can make it better, but it will cost more”; “I can deliver faster, but not with these specs”; or “I can stay strong on cost control, but quality will suffer”? In the new application economy, these tradeoffs are no longer acceptable. Customers will ...

SYS-CON Events announced today that Dyn, the worldwide leader in Internet Performance, will exhibit at SYS-CON's 16th International Cloud Expo®, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY.
Dyn is a cloud-based Internet Performance company. Dyn helps companies monitor, control, and optimize online infrastructure for an exceptional end-user experience. Through a world-class network and unrivaled, objective intelligence into Internet conditions, Dyn ensures...

DevOps is about increasing efficiency, but nothing is more inefficient than building the same application twice. However, this is a routine occurrence with enterprise applications that need both a rich desktop web interface and strong mobile support. With recent technological advances from Isomorphic Software and others, it is now feasible to create a rich desktop and tuned mobile experience with a single codebase, without compromising performance or usability.

Advanced Persistent Threats (APTs) are increasing at an unprecedented rate. The threat landscape of today is drastically different than just a few years ago. Attacks are much more organized and sophisticated. They are harder to detect and even harder to anticipate. In the foreseeable future it's going to get a whole lot harder. Everything you know today will change. Keeping up with this changing landscape is already a daunting task. Your organization needs to use the latest tools, methods and ex...

SYS-CON Events announced today Arista Networks will exhibit at SYS-CON's DevOps Summit 2015 New York, which will take place June 9-11, 2015, at the Javits Center in New York City, NY.
Arista Networks was founded to deliver software-driven cloud networking solutions for large data center and computing environments. Arista’s award-winning 10/40/100GbE switches redefine scalability, robustness, and price-performance, with over 3,000 customers and more than three million cloud networking ports depl...

The speed of software changes in growing and large scale rapid-paced DevOps environments presents a challenge for continuous testing. Many organizations struggle to get this right. Practices that work for small scale continuous testing may not be sufficient as the requirements grow.
In his session at DevOps Summit, Marc Hornbeek, Sr. Solutions Architect of DevOps continuous test solutions at Spirent Communications, will explain the best practices of continuous testing at high scale, which is r...

HP and Aruba Networks on Monday announced a definitive agreement for HP to acquire Aruba, a provider of next-generation network access solutions for the mobile enterprise, for $24.67 per share in cash. The equity value of the transaction is approximately $3.0 billion, and net of cash and debt approximately $2.7 billion. Both companies' boards of directors have approved the deal.
"Enterprises are facing a mobile-first world and are looking for solutions that help them transition legacy investme...

Containers and microservices have become topics of intense interest throughout the cloud developer and enterprise IT communities.
Accordingly, attendees at the upcoming 16th Cloud Expo at the Javits Center in New York June 9-11 will find fresh new content in a new track called PaaS | Containers & Microservices
Containers are not being considered for the first time by the cloud community, but a current era of re-consideration has pushed them to the top of the cloud agenda. With the launch ...

The Workspace-as-a-Service (WaaS) market will grow to $6.4B by 2018. In his session at 16th Cloud Expo, Seth Bostock, CEO of IndependenceIT, will begin by walking the audience through the evolution of Workspace as-a-Service, where it is now vs. where it going.
To look beyond the desktop we must understand exactly what WaaS is, who the users are, and where it is going in the future. IT departments, ISVs and service providers must look to workflow and automation capabilities to adapt to growing ...

As organizations shift toward IT-as-a-service models, the need for managing and protecting data residing across physical, virtual, and now cloud environments grows with it. CommVault can ensure protection &E-Discovery of your data – whether in a private cloud, a Service Provider delivered public cloud, or a hybrid cloud environment – across the heterogeneous enterprise.
In his session at 16th Cloud Expo, Randy De Meno, Chief Technologist - Windows Products and Microsoft Partnerships, will disc...

Skytap Inc., has appointed David Frost as vice president of professional services. David joins Skytap from Deloitte Consulting where he served as Managing Director leading SAP, Cloud, and Advanced Technology Services. At Skytap, David will head the company's professional services organization, and spearhead a new consulting practice that will guide IT organizations through the adoption of DevOps best practices. David's appointment comes on the heels of Skytap's recent $35 million Series D fundin...

Disruptive macro trends in technology are impacting and dramatically changing the "art of the possible" relative to supply chain management practices through the innovative use of IoT, cloud, machine learning and Big Data to enable connected ecosystems of engagement. Enterprise informatics can now move beyond point solutions that merely monitor the past and implement integrated enterprise fabrics that enable end-to-end supply chain visibility to improve customer service delivery and optimize sup...

The speed of product development has increased massively in the past 10 years. At the same time our formal secure development and SDL methodologies have fallen behind. This forces product developers to choose between rapid release times and security.
In his session at DevOps Summit, Michael Murray, Director of Cyber Security Consulting and Assessment at GE Healthcare, examined the problems and presented some solutions for moving security into the DevOps lifecycle to ensure that we get fast AND ...

Even as cloud and managed services grow increasingly central to business strategy and performance, challenges remain. The biggest sticking point for companies seeking to capitalize on the cloud is data security. Keeping data safe is an issue in any computing environment, and it has been a focus since the earliest days of the cloud revolution. Understandably so: a lot can go wrong when you allow valuable information to live outside the firewall. Recent revelations about government snooping, along...

Docker is becoming very popular--we are seeing every major private and public cloud vendor racing to adopt it. It promises portability and interoperability, and is quickly becoming the currency of the Cloud.
In his session at DevOps Summit, Bart Copeland, CEO of ActiveState, discussed why Docker is so important to the future of the cloud, but will also take a step back and show that Docker is actually only one piece of the puzzle. Copeland will outline the bigger picture of where Docker fits a...

Thanks to Docker, it becomes very easy to leverage containers to build, ship, and run any Linux application on any kind of infrastructure. Docker is particularly helpful for microservice architectures because their successful implementation relies on a fast, efficient deployment mechanism – which is precisely one of the features of Docker.
Microservice architectures are therefore becoming more popular, and are increasingly seen as an interesting option even for smaller projects, instead of bein...

The explosion of connected devices / sensors is creating an ever-expanding set of new and valuable data. In parallel the emerging capability of Big Data technologies to store, access, analyze, and react to this data is producing changes in business models under the umbrella of the Internet of Things (IoT). In particular within the Insurance industry, IoT appears positioned to enable deep changes by altering relationships between insurers, distributors, and the insured.
In his session at @Things...

Security can create serious friction for DevOps processes. We've come up with an approach to alleviate the friction and provide security value to DevOps teams.
In her session at DevOps Summit, Shannon Lietz, Senior Manager of DevSecOps at Intuit, will discuss how DevSecOps got started and how it has evolved.
Shannon Lietz has over two decades of experience pursuing next generation security solutions. She is currently the DevSecOps Leader for Intuit where she is responsible for setting and driv...

The Internet of Things has emerged as the universally accepted term for the ‘next big thing’ wave, not replacing but building upon the Cloud Computing cycle, which itself built upon SaaS and ASPs.
There are many technology aspects to this trend, which will be covered extensively throughout this guide and ongoing series, but overall our goal is to describe the associated startup venture opportunities.
Indeed it’s not limited to startups, the IoT represents a new product innovation platform for any and all businesses, and this is the overall theme of this paper.

It’s easy to fall into a pattern of dysfunctional releases, release processes that are characterized by delay, inefficiency, and endless meetings that encourage people to view releases as a problem. These are the kinds of meetings that inspire references to the movie Office Space or emails that include clippings of the cartoon Dilbert - repetitive meetings to answer the same questions over and over again all because people lack the tools to connect the issue tracker with the change management systems.
In organizations without a reliable process a release is also a time for production system o...

A large US insurance carrier, based in the Midwest, has improved its applications’ lifecycle to make enterprise mobility a must-have business strength.
This five-part series of penetrating discussions on the latest in enterprise mobility explores advancements in applications design and deployment technologies across the full spectrum of edge devices and operating environments.
Our next innovation interview focuses on how a large US insurance carrier, based in the Midwest, has improved its applications’ lifecycle to make enterprise mobility a must-have business strength.

In my first blog I wrote about SharePoint System Performance Health Checks beyond looking at CPU and Memory Metrics. In this blog, I cover deployment related performance health problems that I always check when looking at a SharePoint Installation. Especially after deploying new hardware, new sites, pages, views, custom or third-party Web Parts (e.g., from AvePoint, K2, Nintex, Metalogix, etc.) it’s important to perform certain deployment sanity checks. While you may have nobody reporting issues in the moment there are several areas that you constantly need to check before they become a real p...

An anatomy of startup ventures for the Internet of Things market. Like GE describes in their white paper Pushing the Boundaries of Mind and Machine, this is basically a process of innovating through more intelligent machines to reinvent workflow models.
For a useful overview as to what constitutes an ‘IoT startup’, check out one example for some key characteristics: Hutgrip. Hutgrip is a SaaS solution that replaces VPNs with the Cloud and real time analytics, with the headline points being:
Clear description of the business benefit the new technology will bring – Smarter automation of bi...

Containers and microservices have become topics of intense interest throughout the cloud developer and enterprise IT communities.
Accordingly, attendees at the upcoming 16th Cloud Expo at the Javits Center in New York June 9-11 will find fresh new content in a new track called PaaS | Containers & Microservices
Containers are not being considered for the first time by the cloud community, but a current era of re-consideration has pushed them to the top of the cloud agenda. With the launch of Docker's initial release in March of 2013, interest was revved up several notches. Then late last...

DevOps is all about removing barriers to rapid, safe delivery of new experiences to your customers. Much of this revolves around automating error-prone, human-driven processes so that processes can be standardized, scaled, and varied programmatically. Some of the types of tools used in a DevOps-minded organization might include version control systems, automation servers, and configuration management systems. Many tools can be used across categories, with varying amounts of success. Some vendors offer products that claim to address all of these needs with one solution – most rarely deliver on ...

Application metrics, logs, and business KPIs are a goldmine. It’s easy to get started with the ELK stack (Elasticsearch, Logstash and Kibana) – you can see lots of people coming up with impressive dashboards, in less than a day, with no previous experience. Going from proof-of-concept to production tends to be a bit more difficult, unfortunately, and it tends to gobble up our attention, time, and money.
In his session at DevOps Summit, Otis Gospodnetić, co-author of Lucene in Action and founder of Sematext, will share the architecture and decisions behind Sematext’s services for handling larg...

Over the last couple of years I have talked to numerous enterprise customers, analysts, industry pundits, and others interested in cloud technologies, and one thing is abundantly clear – Platform-as-a-Service (PaaS) seems to mean different things to different people. But the term PaaS is irrelevant – it's just noise. What is relevant, and what is important, is what PaaS does: enable applications. That's what enterprises care about. They want to accelerate application development to get products to market faster and into users' hands sooner.

We continue to see an increasing trend in cyber-attacks in line with the growth of new technologies, and enterprises have to protect themselves. It is critical for enterprises to devise their own measures to protect against cyber-attacks because any tolerance on this front is more than an IT issue but may affect the very existence and the business model of the enterprise. We have seen in a recent incident where a cyber-attack prevented a large enterprise from performing their basic business process.

I recently had the opportunity to attend UI19 in Boston, a long-running conference focused on user experience design and ways to be more effective in a UX role as part of a larger team. One of the presentations in particular stuck with me as I returned to Boulder thinking about VictorOps and our evolution as an early stage startup.
Presented by Kim Goodwin, her talk on Principles, Values, and Effective Design Teams touched on a number of challenges we’ve experienced first-hand here at VictorOps as we strive to balance the delivery of a great product with the necessity to move quickly, while...

RealTime Medicare Data analyzes huge volumes of Medicare data and provides analysis to their many customers on the caregiver side of the healthcare sector using HP Vertica.
Here to explain how they manage such large data requirements for quality, speed, and volume, we're joined by Scott Hannon, CIO of RealTime Medicare Data and he's based in Birmingham, Alabama. The discussion is moderated by me, Dana Gardner, Principal Analyst at Interarbor Solutions.

These are some the Key Release Management Metrics our clients use to continually tune their release management process.
1. Number of Changes pending future system releases (Backlog)
2. Number of Successful Changes within a Release
3. Number of Failed Changes in a Release (Percentage of Failed Changes)
4. Number of Outages Caused by a Release
5. Number of Incidents Caused by a Release

It’s become easy to monitor applications that are deployed on hundreds of servers – thanks to the advances in application performance management tools. But the more data you collect the harder it is to visualize the health state in a way that a single dashboard tells you both the overall status as well as the problematic component.
Eugene Turetsky (Dynatrace) and Stephan Levesque (SSQ Financial Group) shared their solution for monitoring large IT infrastructures that contain several hundred components that support SSQ’s most-critical applications running on a variety of technology stacks incl...

DevOps was created to reduce many of these same conflicts and while DevOps has had several high-profile successes it still presents a challenge for larger organizations. Large enterprises managing mission-critical systems still have separate silos for development and operations. In this post I discuss how DevOps fits into the enterprise and what release managers can do to adapt and extend DevOps to meet the challenges present in larger businesses.
First, I’m going to define DevOps. Then I’m going to discuss the impedance mismatch between DevOps and a larger enterprise. In conclusion I’m going...

The competition among public cloud providers is red hot, private cloud continues to grab increasing shares of IT budgets, and hybrid cloud strategies are beginning to conquer the enterprise IT world.

Big Data is driving dramatic leaps in resource requirements and capabilities, and now the Internet of Things promises an exponential leap in the size of the Internet and Worldwide Web.

The world of SDX now encompasses Software-Defined Data Centers (SDDCs) as the technology world prepares for the Zettabyte Age.

Add the key topics of WebRTC and DevOps into the mix, and you have three days of pure cloud computing that you simply cannot miss.

Cloud Expo - the world's most established event - offers a vast selection of 130+ technical and strategic Industry Keynotes, General Sessions, Breakout Sessions, and signature Power Panels. The exhibition floor features 100+ exhibitors offering specific solutions and comprehensive strategies. The floor also features two Demo Theaters that give delegates the opportunity to get even closer to the technology they want to see and the people who offer it.

Attend Cloud Expo. Craft your own custom experience. Learn the latest from the world's best technologists. Find the vendors you want and put them to the test.